/*
 * Copyright 2011-2020 GatlingCorp (https://gatling.io)
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package io.gatling.commons.util

object Collections {

  implicit class PimpedTraversableOnce[A](val t: TraversableOnce[A]) extends AnyVal {

    def sumBy[B](f: A => B)(implicit num: Numeric[B]): B = {
      var sum = num.zero
      for (x <- t) sum = num.plus(sum, f(x))
      sum
    }
  }

  def lift[T](it: Iterator[T], i: Int): Option[T] = {
    var j = 0
    var found: Option[T] = None
    while (it.hasNext && found.isEmpty) {
      val value = it.next()
      if (i == j) {
        found = Some(value)
      }
      j += 1
    }
    found
  }
}
